How 'bout you?
If the US Army has no more responsibilities in terms of defending the borders than the current Border Patrol does, then no, I'm not in favor of it. If there is an actual danger of a military incursion, then the military should certainly repel it. I doubt that I'll see the Mexican or Canadian armies streaming across the border in an actual invasion in my lifetime though.
Our military is trained for dealing with actual combatants. I'd just as soon not expand their mission to dealing with wetbacks and drug smugglers.